1. Field of the Invention
The present invention relates to a window system and light guiding film therein, and more particularly to a window system and light guiding film capable of changing the direction of incident light.
2. Description of the Related Art
The conventional sunlight guiding apparatus is of various types, such as plate, shutter or film, which is disposed on or near a window of a room and used for guiding sunlight beams into the room. The sunlight beams are directed to illuminate a reflector on the ceiling in the room. The sunlight beams are then reflected by the reflector, and used for indoor lighting or auxiliary illumination. In some conventional sunlight guiding apparatus, the sunlight beams are guided into the room directly without being reflected by the reflector on the ceiling.
The conventional sunlight guiding apparatus can guide the direct light beams and the diffused light beams of the sunlight to the reflector on the ceiling by retraction and/or reflection, so as to illuminate the interior of the room uniformly and reduce discomfort from glare. Further, the use of the conventional sunlight guiding apparatus can save energy required by daytime use of electric lighting equipment.
The drawback suffered by conventional sunlight guiding apparatus is described as follows. Most of the sunlight beams cannot be directed to the ceiling; that is, most of the sunlight beams cannot be reflected by the reflector in order to effectively resolve the problem of glare. Thus, the illumination effect is not ideal.
Therefore, it is necessary to provide a window system and light guiding film therein to solve the above problems.